Recently I had to reinstall Ubuntu studio 18.04 to “fix” some problems I didn’t know how to deal with. I’ve always used the Pascal de Bruijn “fairly stable” ppa to get an updated Darktable release. I happened to notice that the Software center had Darktable 2.6.2 available as a Snap package. The “fairly stable” ppa release is Darktable 2.6.1, so I tried the Snap version. Now it’s entirely possible that I may have done something wrong but when I checked to see if opencl was working , I found the “not available” message. I have all the Nvidia libraries installed same as always but no opencl with the Snap package. So I got rid of it and installed the trusty ppa and all is well again.

It’s not a big deal to me to have 2.6.1 running instead of 2.6.2, but my curiosity has the better of me here. I couldn’t find anything out there about Darktable snap and opencl, so I figured I’d see what our forum has to say here.

How do I know if I have a snap package (Linux 18.04). I checked with Software Manager and it states Source Local. I’m asking because Darktable tells me activate OpenCL support not available. Video card is a Nvidia GTX 1050. Nividia X server settings Driver version 390.116 (OpenGL?).

…and i don’t know anything about snap packages. but to be able to ship opencl enabled binaries, we dynamically dlopen() all library functions manually (i.e. we don’t link against the library, which would mean we’ll have a compile time dependency). this means you should be able to just run dt on a system with libOpenCL.so and the stuff around it and it should go and pick it up.

That’s great that you got your opencl working. You can try tweaking some things in your .config/darktablerc file as well. For me, by simple trial and error, I found that changing “opencl_number_event_handles” to 150 and “opencl_memory_headroom” to 400 works best for my hardware. The export times and the “working” times when applying a new module are way faster than without the opencl active.